Light altering device

ABSTRACT

A line producing system includes an input beam of radiant energy that enters a side of a low cost, radiant energy altering device. The radiant energy emerges from the light altering device radiating in a nearly 360 degree disc pattern forming a ring of ever expanding light.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This is a divisional of U.S. application Ser. No. 09/728,756filed Dec. 04, 2000 by the same inventor, and claims priority therefrom.This divisional application is being filed in response to a restrictionrequirement in that prior application and contains rewritten and/oradditional claims to the restricted subject matter.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to the field of radiation manipulation. Inparticular, the invention relates a method and apparatus for altering abeam of light or radiant energy.

[0004] 2. Description of Related Art

[0005] Heretofore, light has been manipulated to produce an alignmentfield with laser based equipment as shown in U.S. Pat. No. 3,588,249where a collimated laser beam is rotated 360 degrees about an axis toestablish an alignment plane. Remote receivers in the vicinity maydetect the laser beam as it sweeps past, and provide a visual or audibleindication when they are aligned in the laser plane. While this rotatingbeacon technique provides results that are quite useful over longranges, the cost of the mechanical and optical structures forimplementing the technique with the desired amount of accuracy isrelatively high. Also, the plane is more difficult to locate if thereceiver is moved through the plane before the beam strikes itsdetector.

[0006] An improvement is disclosed in U.S. Pat. No. 4,674,870 thatincludes a laser alignment system employing a transmitter and one ormore receivers. The transmitter produces an alignment field byprojecting laser energy in a non-planar reference cone, and thereceivers locate this reference cone with photodetectors. The laserenergy in the alignment field is modulated at 8 kHz and the signalsproduced by the photodetectors are filtered and amplified to increasethe range of the system. Each receiver operates a display, whichindicates when it is aligned in the reference cone, and it produces anout-of-level indication when the transmitter is not properly aligned.

[0007] A transmitter for an alignment system is shown in U.S. Pat. No.4,679,937 in which a field of electromagnetic radiation is propagated ina non-planar reference cone. The transmitter includes a source forproviding a collimated beam of electromagnetic radiation directedparallel to a beam axis. A cantilever strand supports a bob within thebeam. The bob has a conical reflection surface to reflect the collimatedbeam conically. Optimally, the cantilever stand and bob are chosen toprovide a deflection between the bob and plumb which is substantiallyone-half of any angular error between the beam axis and plumb. In apreferred form, a housing surrounds the bob and has inner and outersurfaces, which minimize temperature effects on the orientation of thereference plane. In addition, detectors are provided to sense when theangular error between the beam axis and plumb is outside of anacceptable range. Other leveling devices are shown in U.S. Pat. Nos.5,914,778; 5,940,557; 5,994,688; 6,005,719 and 6,009,630.

[0008] Obviously, in view of the above prior art, there is still a needfor a cost effective level line system.

SUMMARY OF THE INVENTION

[0009] Accordingly, in one aspect of the present invention, a low cost,light-altering device in the form of a hollow tube is disclosed for usein an optical level line system. The system includes an input beam oflight or radiant energy that enters a side of the hollow glass tube.Light emerges from the tube radiating in a nearly 360 degree discpattern forming a disc of ever expanding light. When the light strikesan enclosed or circular surface, a bright line or ring of light isproduced on the surface. This ring can be generated for X, X and Y, andX, Y, and Z axes, by employing an individual light-altering device peraxis, thereby supplying a line or ring for each axis. The lines or ringsof light are ideally suited, for example, for laser line levelingapplications.

[0010] In another aspect of the present invention, an input beam oflight or visible radiation enters a side of a light-altering device inthe form of a capillary array of small tubes. The light emerges from thearray radiating in a nearly 360 degree disc pattern forming a disc ofever expanding light. When the light strikes an enclosed surface, abright line or ring of light is produced on the surface. This ring canbe generated for X, X and Y, and X, Y, and Z axes, by employing anindividual light-altering device per axis, thereby supplying a line orring for each axis.

[0011] In a third aspect of the present invention, an input beam oflight or visible radiation enters a side of light altering devicecomprising a fiber optic rod. The light emerges from the rod radiatingin a nearly 360 degree disc pattern forming a disc of ever expandinglight. When the light strikes an enclosed surface, a bright line or ringof light is produced on the surface. This ring can be generated for X, Xand Y, and X, Y, and Z axes, by employing an individual light-alteringdevice per axis, thereby supplying a line or ring for each axis.

[0012] In a fourth aspect of the present invention, a low cost, lightaltering device is disclosed for use in an optical level line system.The system includes an input beam of light or visible radiation thatenters a side of the light altering device that includes a hollow tubewithin a hollow tube. The light emerges from the tubes radiating in anearly 360 degree disc pattern forming a disc of ever expanding light.When the light strikes an enclosed surface, a bright line or ring oflight is produced on the surface. This ring can be generated for X, Xand Y, and X, Y, and Z axes, by employing an individual light-alteringdevice per axis, thereby supplying a line or ring for each axis.

[0013] These and other features and advantages of the invention aredescribed in or apparent from the following detailed description on theexemplary embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The foregoing and other features of the instant invention will beapparent and easily understood from a further reading of thespecification, claims and by reference to the accompanying drawings inwhich:

[0015]FIG. 1 is a top view of an exemplary embodiment of a lightaltering device in accordance with the present invention that employs ahollow tube, rod or capillary member(s).

[0016]FIG. 2 is a top view of another exemplary embodiment of alight-altering device in accordance with the present invention thatemploys a capillary array.

[0017]FIG. 3 is a top view of yet another exemplary embodiment of alight altering device in accordance with the present invention thatemploys a hollow tube within a hollow tube.

[0018]FIG. 4 is a top view of yet another exemplary embodiment of alight altering device in accordance with the present invention thatemploys a fiber optic rod.

[0019]FIG. 5 is a top view of still another exemplary embodiment of alight altering device in accordance with the present invention thatemploys a gap between a rod and a reflecting plane.

[0020]FIG. 6 is a top view of another embodiment of the presentinvention that is adaptable to produce a light reference plane of lessthan 360 degrees.

[0021]FIG. 7 is a side view of a light-altering device in accordancewith the present invention that employs a plumb bob.

[0022]FIG. 8 is yet another embodiment of the light altering device ofthe present invention employing a concave or convex shaped reflector.

[0023]FIG. 9 is an embodiment of a light altering device of the presentinvention that employs a concave, conical or parabolic reflector havinga hole cut in its side to allow the projection of light.

DETAILED DESCRIPTION OF THE INVENTION

[0024] In accordance with the present invention, a novel Light AlteringDevice (LAD) and method is disclosed to alter a beam of light or radiantenergy from laser sources. This LAD dramatically changes an input beamof light or radiant energy's properties. As an example, a laser beamentering the LAD is altered such that the light emerges radiating in asubstantially 360 degree disc pattern. This pattern can be obtainedemploying a variety of materials and geometries. One exemplaryembodiment of the present invention employing a LAD is shown in FIG. 1.Here, a laser beam 12 of laser 10 is shown entering the side of a LAD 15in the form of a hollow glass tube 16. Light emerges from tube 16radiating in the direction of arrows 11 in a 360 degree disc pattern 17.Thus, a disc is formed of ever emerging light. An enclosure, forexample, a circular screen placed a given radius from the tube willallow an observer to view a bright ring of light on the screen surface.In addition, the uniformity of the light distribution around the radiusis quite uniform. The light ring still maintains the optical propertiesof the directed beam. That is, polarization of the directed beam remainsthe same around the radius of the ring of light. Also, if the directedbeam is such that it is focussed to a point 3 meters from where the tubemay be inserted, when the tube is inserted the focal point remainsrelatively unchanged.

[0025] A tube 16 made of glass, plastic, gelatin, etc., with the properdiameter, wall thickness, index of refraction, etc., with a red laserinput, can produce an emerging dotted ring of red light. That is, ablack and red series of dots (dashes) around the disc will result. Theinterference and/or diffraction properties of light are responsible forthis effect.

[0026] In another embodiment of the present invention in FIG. 2, LADdevice 15 includes a capillary array 20 of hollow glass tubes. As shown,laser beam 12 of laser 10 enters a side of capillary array 20 with lightradiating from the capillary array in a disc pattern of about 360degrees. Thus, again a disc is formed of ever emerging light 17 in thedirection of arrows 11. A circular screen placed a given radius from thearray will again allow an observer to view a bright ring of light 17 ona surface of the screen.

[0027] In the embodiment of the present invention shown in FIG. 3, laser10 directs an input laser beam 12 into a surface of LAD 15 whichcomprises a combination of hollow tubes 30 and 31, with hollow tube 30placed within hollow tube 31. As a result, light radiates from thehollow tubes 30 and 31 in a disc pattern of approximately 360 degreesforming an ever emerging light 17 in the direction of arrows 11. Acircular screen placed a given radius from the tubes will again allow anobserver to view a bright ring of light 17 on a surface of the screen.

[0028] In the embodiment of the present invention shown in FIG. 4, laser10 directs an input laser beam 12 into a surface of LAD 15 whichcomprises a fiber optic rod 25. As a result of laser beam 12 strikingthe surface of fiber optic rod 25, light radiates from the rod in thedirection of arrows 11 in a disc pattern of approximately 360 degreesforming an ever emerging ring of light 17. A circular screen placed agiven radius from the tubes will again allow an observer to view abright ring of light 17 on a surface of the screen. A fiber optic rod 6mm in diameter displays a fairly uniform brightness around the rod wherethe beam enters. This scattered light seems uniform and so does theemerging beam. However, there is no visible light emerging from eitherof the polished ends of the rod. Therefore, there is minimal light lossinto the fibers, thereby indicating an efficient reflection at thecladding interface. It is believed that there are multiple reflectionswithin and/or around the outside of the fiber optic rod. The light, inthis case, reflects off small micron diameter fibers, for example, about13 microns, all encircling and contained in the ¼ inch diameter fiberoptic rod, without a significant drop in light energy. That is, thetotal power emitted by the fiber optic rod is quite close to the powerof the light directed into the rod. However, some scattered light isnoticed around the circumference of the rod, but is only as wide as theentering light beam and does not appear to be very significant.

[0029] A method for efficiently utilizing almost all of the lightgenerated, while providing a beam over 180 degrees or so, isaccomplished by employing a light altering-device in contact with aglass surface contacting a mirror with a hole through it. In theembodiment of the present invention shown in FIG. 5, a laser 10 directsa laser input beam 12 through a channel 16 cut through mirror 13. Laserbeam 12 enters a glass member 14 as it is directed towards LAD 15 in theform of a fiber optic rod 18. Glass 14 serves as a spacer member toforce a controlled and parallel gap between LAD 15 in the form of fiberoptic rod 18 and reflecting plane 19 of mirror 13. As shown by arrows11, some light is reflected off the glass surface, while other rays oflight are directed toward the mirror, striking the mirror, andreflecting off the mirror in multiple directions whereby it ismulti-reflected to provide an emerging semi-circular beam of 180degrees, or so. All of these reflections occur in the same plane thatthe beam strikes the LAD. Of course, using a mirror without a hole orchannel can be employed by aiming the laser-input beam directly at theLAD from the side. That is, at an angle slightly greater than 90 degreesfrom the laser beam 12 shown in FIG. 5.

[0030] It should be understood that other methods may be employed toalter light beams for special purposes or special results. For example,to improve beam uniformity about its circumference, mirrored coatingsmay be applied to the appropriate regions on the outer surfaces of therod or tube(s) to direct light to the less bright regions of the beam.Also, the altering of the cross-sectional shape of the rod or tube to beoval, spherical, or have a flat areas on the circumference, etc., canprovide special beneficial light patterns.

[0031] LAD units may also employ light sources other than lasers forillumination sources. This can include point or line sources, singlecolors, white light, etc. In fact, for special applications, multiplelaser or light sources can be employed such that each individual sourceis aimed directly into a single LAD, without the light losses typicallyassociated with uniting multiple light beams.

[0032] Hereinbefore, a LAD has been described that produces nearly a 360degree circle of light. In some instances, there are times when it ispreferable to employ only a portion of a circle of light, for example,90 to 180 degrees for line making purposes. In those instances, theembodiment of the present invention shown in FIG. 6 is employed thatcomprises a substrate 55 with a channel 16 therein and is aligned toanother substrate 57 orthogonally. LAD 15 is positioned at anintersection of substrates 55 and 57 on top of a mirrored face 13 of thesubstrates. In this configuration, a 90 degree portion of a circle iscreated by a beam 12 from laser 10 applied through channel 16 insubstrate 55. The laser beam contacts LAD 15 and light emerges from theLAD, as shown by lines 17, initially in all directions as shown byarrows 11. However, mirrors 13 redirect the light such that it iscontained approximately within the 90 degrees formed by the mirrors. Bymoving mirror 57 relative to mirror 55 a larger angular coverage can beattained as shown by arrow 58. It should be understood that substrates55 and 57 could be made of glass with mirrors 13 being placed on theopposite face of the substrates.

[0033] In FIG. 7, a plumb bob laser leveling apparatus 60 is shown thatincludes a LAD 15 positioned within plumb bob 62. Spherical plumb bob 62is fashioned having two hemispheres separated by a narrow transparentmember 64 which encompasses the 360 degrees of the sphere's equator. ALAD 15 is positioned within the space provided between the two halves ofthe bob in order to provide a circle of light. The bob can be suspendedfrom a string, a flat metal tape, e.g., a measuring tape in conjunctionwith a metal ring 69, or attached to a wall, suspended from a door frameor ceiling, or operate hanging from a cross arm rod attached to a baseor cantilevered from the base resting on a floor. The bob can have mostany shape and is unique in that it automatically rests in a straightdown position. This principle dictates that a plane cut through the boborthogonal to the string direction can be useful for floor leveling.Thus, a LAD unit properly aligned/positioned within the bob allows theLAD to produce a circle of light for reference purposes, e.g., toachieve floor flatness. While it is preferred to center the weightdistribution of the laser and LAD within the housing of the bob andspacer members, it may not be critical, since it should be much lessthan the mass of the bob. The bob weight can significantly dominate overthe weight distribution of the LAD.

[0034] In operation, laser 10 supplies a beam of light 12 onto mirror 65that deflects the light in a straight line into LAD 15. The laser beamemerges from LAD 15 as an ever-expanding ring of light in the directionof arrows 11. For best results, the mirror should be slightly wider thanthe beam width.

[0035] Concave and convex cylindrical reflectors can be useful forgenerating unique light patterns. In the method and apparatus shown inFIG. 8, laser beam 12 of laser 10 passes through a hole in the concaveand cylindrical reflector 70 to strike LAD 15. As the ever expandinglight emerges in the direction of arrows 79, some of it strikes andreflects off mirrored surface 71 of the concave reflector 70. Mirroredsurface 71 is mounted on a glass substrate 74. The remaining lightcontinues until it emerges at an angular extent that is determined bythe parameters between the LAD 15 and mirrored reflector 71. That is,altering the reflector's shape, size, focal point, length, curvature,etc., allows for obtaining any desired angular extent required. Forexample, the reflector's angular extent could be altered by cutting itoff at marks 72 and 73. Since the reflected light combines with theemerging light in the same plane, the emerging ring segment brightnessis increased and made more uniform. Alternatively, a convex cylindricalreflector 78 shown in dotted lines may be employed to control theangular extent of the emerging light disc and function to give a widerangle of reflection.

[0036] Incorporating a LAD 15 on the optical axis of a concave, conicalor parabolic reflector 80 having a slot (or hole) cut into its side isillustrated in FIG. 9. A laser beam 12 from laser 10 is directed throughthe slot striking LAD 15 producing a ring of light 17 that in turnstrikes the inside of reflector 80. The light ring is reflected andconverged and then diverges, as shown by arrows 11, to strike a polishedsurface 86 of cone 85 placed on an axis with the reflected beam. Thering of light after reflection from surface 86 of cone 85 is directed soas to be parallel to the ground, thereby enabling its use for levelreferencing purposes. With the structure fabricated within a bob, by itsnature, the unit would be self leveling.

[0037] Other light altering devices may be constructed with monofilamentfish line, single or multiple optical fibers, thin wires, or numerousother thin filament materials. These elements may be operated in vacuum,air, and be used in liquids, plastics, and glass and employed with orwithout cladding and/or covering materials. It is also contemplated thatthe cross sectional shapes of the aforementioned light altering devicesmay be altered for special purposes and that reflective coatings mayalso be applied to the light altering devices for special usages, forexample, to improve emerging beam uniformity and efficiency.

[0038] It should now be understood that a low cost, radiant energyaltering device has been disclosed that is a few millimeters in diameterand changes an input beam of radiant energy into an output in a discpattern. The radiant energy altering device is low in cost and cancomprise a variety of materials and geometries, including hollow glasstubes, fiber optic rods, tubes within tubes, etc. The altering device isnot limited to input of laser energy, be it coherent or incoherent,multiple wavelength, i.e., broadband, colored or white, point or linesource.

[0039] While the invention has been described in conjunction with thespecific embodiments outlined above, it is evident that manyalternatives, modifications and variations will be apparent to thoseskilled in the art. Accordingly, the preferred embodiments of theinvention as set forth above are intended to be illustrative and notlimiting. Various changes may be made without departing from the spiritand scope of the invention as defined herein.

What is claimed is:
 1. A line producing apparatus, comprising: a lasersource adapted to produce radiant energy; a laser output alteringdevice, and wherein radiant energy projected from said laser source intosaid laser output altering device emerges from said laser outputaltering device in a predetermined plane; and a plumb bob with saidlaser output altering device positioned between portions of said plumbbob.
 2. The apparatus of claim 1, including a mirror, and whereinradiant energy from said laser source is projected into said mirror andthen into said laser output altering device.
 3. The apparatus of claim2, wherein said mirror is angled with respect to radiant energy emergingfrom said laser source.
 4. The apparatus of claim 1, wherein said laseroutput altering device is in the form of a hollow tube.
 5. The apparatusof claim 1, wherein said laser output altering device is in the form ofa hollow tube within a hollow tube.
 6. The apparatus of claim 1, whereinsaid laser output altering device is in the form of a fiber optic rod.7. The apparatus of claim 1, wherein said reflecting surface of saidmirror is spaced from said laser output altering device.